1. Field of the Invention
The present invention relates to a context-base input/ output system and, more particularly, to a context-base input/output system for inputting a manually drawn sketch to a computer to convert it into a geometrically defined pattern and to display it.
2. Description of the Prior Art
Generally speaking, pattern input to the computer is accomplished by means of an electronic pen, a digitizer, a mouse or the like after either a menu (i.e., a table indicating the functions) on the screen of a CRT or a tablet menu on a tablet has been selected. In case a circle is to be displayed on a CRT by means of the electronic pen and the tablet, for example, the function to display the circle is selected from the menu, and a data corresponding to a central point of the circle and one point on its circumference are registered at a predetermined position of the tablet by means of the electronic pen. Then, the computer executes graphic processing to display the circle according to the input data on the CRT. According to a method using the tablet menu, on the other hand, difference from the foregoing method is limited to a point that the selection of function from the menu is executed on the tablet.
However, the aforementioned methods of selecting the graphic processing function according to the menus suffer from problems that a number of steps of selecting the function from the menu is more than a method of manually drawing a segment or circle directly on a paper by writing means so that they are not only troublesome but also felt with a physical disorder, thus making it difficult to use the tool. Moreover, the method of inputting the data is executed by inputting the data of specific points and is followed by the feeling of a physical disorder because operations are different from those in case the pattern is manually drawn.